Process for crosslinking of ethylene/acrylic ester copolymers

ABSTRACT

Disclosed is a process for crosslinking copolymers of ethylene and acrylic esters by converting some of the ester groups to ester or amide groups which contain unsaturation, and then sulfur or peroxide curing the resulting polymers. The resulting crosslinked polymers often have excellent vulcanizate properties, and are useful especially in elastomeric form as seals and gasket.

This application claims the benefit of provisional application60/186,603 filed Mar. 3, 2000.

FIELD OF THE INVENTION

Copolymers of ethylene and acrylic esters are crosslinked by convertingsome of the ester groups to ester or amide groups which containunsaturation and then sulfur or peroxide curing the resulting polymers.

TECHNICAL BACKGROUND

Crosslinking (also sometimes termed vulcanization or curing) of polymersyields products which often have improved properties for their intendeduses. This is particularly true when the polymer is an elastomer, andcuring of elastomers is very commonly done, for instance using sulfur orperoxide curing. For sulfur cures, generally speaking the polymercontains olefinic unsaturation, while for peroxide curing the presenceof olefinic unsaturation is often preferable, see for instance H. Mark,et al., Ed., Encyclopedia of Polymer Science and Engineering, Vol. 17,McGraw-Hill Book Co., New York, 1989, p. 666-698.

However, some types of elastomers do not contain olefinic unsaturation,and so are not generally sulfur cured, and/or cured by peroxides withsome difficulty. These elastomers are cured using other curing systems.For example, elastomeric ethylene/acrylic copolymers may be crosslinkedby the use of primary diamines, which form crosslinks, see for instanceH. Mark, et al., Ed., Encyclopedia of Polymer Science and Engineering,Vol. 1, McGraw-Hill Book Co., New York, 1985, p. 325-334. In order toaid in such crosslinking to more readily form crosslinks and/or formmore stable crosslinks curesite monomers, such as carboxylic acids orhalf acid esters may be copolymerized into the polymer, see for instanceU.S. Pat. Nos. 3,883,472 and 3,904,588. However, it is often desirableto crosslink such polymers using sulfur or peroxide cures, because suchcures are already in use in many factories for a wide variety of commonelastomers, and/or the curing agents are less expensive and/or lesstoxic. In order to make such types of polymers peroxide and/or sulfurcurable, it is desirable to introduce into them olefinic unsaturationcontaining groups. These groups should be introduced in such a way so asnot to harm the basic polymer properties, so that the polymers may bereadily and/or economically cured, and/or the resulting crosslinks arestable (so as to give good vulcanizate properties).

Japanese Patent Application 62-121746 describes the esterification of apolymer made from ethylene, an acrylic ester and maleic anhydride and/ora maleic half acid ester which is “modified” with an olefinicallyunsaturated amine or alcohol, and then cured using a sulfur or peroxidecure. No mention is made of polymers containing only ethylene andacrylic ester repeat units.

German Patent Application 3,715,027 A1 describes various copolymers ofethylene and acrylic acids and/or esters, and optionally other monomerssuch as maleic anhydride, their reaction with olefinic alcohols,including those with polyunsaturation, and their subsequent crosslinkingby oxidation, e.g., reaction with air, often in the presence of anoxidation catalyst. The polymers are useful as thermosetting meltadhesives. No mention is made of sulfur or peroxide curing.

U.S. Pat. No. 5,736,616 is similar to German Patent Application3,715,027, in that a polymer containing pendant unsaturation is used asan oxygen scavenger (react with oxygen). The polymer is made bypolymerizing ethylene and acrylic esters and/or acids and thenesterifying or transesterifying the resulting polymer with anunsaturated alcohol. No mention is made of curing such a polymer using asulfur or peroxide cure.

U.S. Pat. No. 5,093,429 describes the preparation of a polymercontaining olefinic unsaturation by direct copolymerization of ethylene,an acrylic ester, and a copolymerizable monomer containing unsaturationwhich survives the polymerization (for example has a copolymerizabledouble bond and a double bond which is unreactive in thepolymerization), or by copolymerization of ethylene, and acrylic ester,and another copolymerizable monomer which may then be reacted with anunsaturated alcohol or amine to attach such unsaturation to the polymer.The polymer containing unsaturation may then be crosslinked using asulfur or peroxide curing system. No mention is made of using theacrylic ester as a site to attach the olefinic unsaturation.

In some instances the crosslinks that result from curesite monomerspresent in some of the above references are not as stable as desiredbecause linkages between the crosslinkable groups (e.g., olefinicunsaturation) are not as stable as desired (for example U.S. Pat. No.4,399,263 mentions that at temperatures above 160° C. ethylene/alkylacrylate/maleic acid ester polymers form anhydride moieties by internalreaction at the acid-ester curesite). The crosslinks may not besufficiently stable because the curesite monomers and/orpolymer-modifying reagents, which attach curable functionalities ontothe polymer, introduce groups into the composition which catalyzeunwanted reactions.

SUMMARY OF THE INVENTION

This invention concerns a process for crosslinking a polymer,comprising:

(a) transesterifying or amidating a first polymer consisting essentiallyof about 10 or more mole percent of ethylene, about 10 or more molepercent of

and up to about 10 mole percent, total, of one or more hydrocarbonolefins, with an alcohol or a primary amine which contains one or moreolefinic bonds, to form a second polymer having side chains with saidolefinic bonds; and

(b) crosslinking said second polymer using a sulfur or peroxide curesystem;

and wherein:

R¹ is methyl or hydrogen; and

R² is hydrocarbyl or substituted hydrocarbyl.

Also disclosed herein is a composition comprising:

(a) a polymer made by transesterifying or amidating a first polymerconsisting essentially of about 10 or more mole percent of ethylene,about 10 or more mole percent of

and up to about 10 mole percent, total, of one or more hydrocarbonolefins, with an alcohol or a primary amine which contains one or moreolefinic bonds, to form a second polymer having side chains with saidolefinic bonds; and

(b) a sulfur or peroxide cure system;

and wherein:

R¹ is methyl or hydrogen; and

R² is hydrocarbyl or substituted hydrocarbyl.

Another composition disclosed herein comprises:

(a) a polymer consisting essentially of about 10 or more mole percent ofethylene, about 10 or more mole percent of

and up to about 10 mole percent, total, of one or more hydrocarbonolefins; and

(b) a sulfur or peroxide cure system;

and wherein:

R¹ is methyl or hydrogen; and

R² is hydrocarbyl or substituted hydrocarbyl, provided that at least 0.5mole percent of R² contains olefinic unsaturation.

DETAILS OF THE INVENTION

Herein certain terms are used, and they are defined below.

By hydrocarbyl is meant a univalent radical containing only carbon andhydrogen. Unless otherwise specified it is preferred that it contain 1to 30 carbon atoms.

By substituted hydrocarbyl is meant hydrocarbyl containing one or moresubstituents (functional groups) which do not interfere with (asappropriate) amidation, transesterification and crosslinking. Usefulsubstituents include oxo (keto), halo, ether and thioether. Unlessotherwise specified it is preferred that it contain 1 to 30 carbonatoms.

By a hydrocarbon olefin is meant a polymerizable olefin containing onlycarbon and hydrogen.

By olefinic double bond is meant a carbon-carbon double bond which isnot part of an aromatic ring. Preferably the olefinic double bond hasone or more allylic hydrogen atoms, particularly when a peroxide cure isused.

By an acrylic ester is meant a compound of formula (I).

By a dipolymer is meant a copolymer containing repeat units derived fromtwo monomers.

By a sulfur cure system is meant any of the conventional known curesystems that cure unsaturated polymers using sulfur chemistry, see forinstance H. Mark, et al., Encyclopedia of Polymer Science andEngineering, Vol. 17, McGraw-Hill Book Co., New York, 1989, p. 666-698,and W. Hoffmann, Vulcanization and Vulcanizing Agents, MacLaren & Sons,Ltd., London, 1967, both of which are hereby included by reference. Thecure system may include conventional accelerators and other compounds,and may or may not have free sulfur present.

By a peroxide cure system is meant any of the conventional known curesystems that cure unsaturated polymers (they may also cure polymerscontaining no unsaturation) using organic peroxides, see for instance W.Hoffmann, Vulcanization and Vulcanizing Agents, MacLaren & Sons, Ltd.,London, 1967, which is hereby included by reference. Besides theperoxide being present, other conventional ingredients such as so-calledcoagents may also be present.

By elastomeric or an elastomer is meant that the heat of fusion of anypolymer crystallites present with a melting point (Tm) of 50° C. or moreis less than 5 J/g, more preferably less than about 2 J/g, andpreferably no polymeric crystallites are present at 25° C., and that theglass transition temperature (Tg) of the polymer is less than about 50°C., more preferably less than about 20° C., and especially preferablyless than about 0° C. The Tm and heat of fusion of the polymer aredetermined by ASTM method D3451 at a heating rate of 10° C./min and theTm is taken as the peak of the melting endotherm, while the Tg of thepolymer is determined using ASTM Method E1356 at a heating rate of 10°C./min, taking the midpoint temperature as the Tg. Both of these aredetermined on a second heating of the polymer.

Preferably the first polymer used in the present invention is adipolymer of ethylene and (I). In (I) it is preferred that R¹ ishydrogen and/or R² is hydrocarbyl, more preferably alkyl containing 1 to6 carbon atoms, and especially preferably methyl [when R¹ is hydrogenand R² is methyl, (I) is methyl acrylate]. Also preferably the firstpolymer is elastomeric. A particularly preferred polymer is anethylene/methyl acrylate dipolymer containing about 13 to about 46 molepercent of methyl acrylate.

Useful hydrocarbon olefins include styrene, α-methylstyrene, andsubstituted styrenes.

Useful alcohols which contain olefinic bonds include alcohols of theformula H(CH₂)_(p)CH═CH(CH₂)_(q)CH₂OH, (II), wherein p is 0 or aninteger of 1 to 10, and q is 0 or an integer of 1 to 30,HR³(CR⁴═CR⁵R⁶)_(t)CH₂OH (III) wherein R³ and each R⁵ are eachindependently a covalent bond, alkylene or alkylidene, and R⁴ and R⁶ areeach independently hydrogen or alkyl, wherein (when applicable) R³, R⁴,R⁵ and R⁶ each independently contain 1 to 20 carbon atoms, and t is 1, 2or 3. (II) is a preferred alcohol, and in (II) it is preferred that p is0 and/or q is 5 to 17, or p is 8 and q is 7. It is preferred that thesealcohols be primary or secondary alcohols, and more preferred that theybe primary alcohols. Mixtures of alcohols may be used, for example amixture of oleyl, linoleyl and linolenyl alcohols. Specific preferredalcohols include 10-undecen-1-ol, oleyl alcohol,cis-3,7-dimethyl-2,6-octadien-1-ol and 3-methyl-2-butenol.

Useful primary amines which contain olefinic bonds include amines of theformula H(CH₂)_(p)CH═CH(CH₂)_(q)CH₂NH₂, (IV), wherein p is 0 or aninteger of 1 to 10, and q is 0 or an integer of 1 to 30,HR³(CR⁴═CR⁵R⁶)_(t)CH₂NH₂ (V) wherein R³ and each R⁵ are eachindependently a covalent bond, alkylene or alkylidene, and R⁴ and R⁶ areeach independently hydrogen or alkyl, wherein (when applicable) R³, R⁴,R⁵ and R⁶ each independently contains 1 to 20 carbon atoms, and t is 1,2 or 3. (IV) is a preferred primary amine, and in (IV) it is preferredthat p is 0 and/or q is 5 to 17, or p is 8 and q is 7.

Since the reaction of the unsaturated alcohol or primary amine with thefirst polymer is usually run at elevated temperatures, and it ispreferable that the alcohol or amine not be volatilized before it has achance to react with the first polymer, it is preferred that the boilingpoint of this compound be high enough so that volatilization will berelatively slow. This of course means that the molecular weight of theamine or alcohol be such that the boiling point is relatively high. Thusit is preferred that the atmospheric boiling point (if necessaryextrapolated from a boiling point at lower pressure) of the unsaturatedprimary amine or unsaturated alcohol be above the process temperature,more preferably at least about 50° above, for reaction of the firstpolymer [step (a)]. The olefinically unsaturated alcohol is a preferredreactant with the first polymer.

The first polymer is reacted with an olefinically unsaturated alcoholand/or primary amine to form a polymer in which the olefinicallyunsaturated alcohol and/or primary amine becomes a side chain on thepolymer (forming the second polymer). If an alcohol is used, atransesterification takes place, replacing the —OR² group with a groupderived from the alcohol (the alcohol minus the hydroxyl hydrogen atom).If a primary amine is used, an amidation takes place, replacing the —OR²group with a group derived from the primary amine (the primary amineminus one of the hydrogen atoms on the amino nitrogen atom). The totalamount of alcohol and/or amine added to the reaction with the firstpolymer will depend upon the degree of transesterification and/oramidation desired and the percentage of alcohol and/or primary amineactually reacted with the first polymer. Typically this will range from0.1 to 100 mole percent of the repeat units (I) present in the firstpolymer used, preferably 0.1 to about 50 mole percent, more preferablyabout 0.1 to about 35 mole percent, and especially preferably about 1 toabout 20 mole percent of (I). To increase the rate of reaction, theamount of alcohol and/or amine added can exceed 100% of (I), but thismay have other consequences (see below).

The reaction of the first polymer may be carried out at any temperatureat which the transesterification and/or amidation takes place, a rangeof about 100° C. to about 350° C., preferably about 140° C. to about280° C., and more preferably about 180° C. to about 260° C., beinguseful. The temperature should preferably not exceed a temperature atwhich significant decomposition of the polymer takes place. Thetemperature which is needed may be affected by the use of a catalyst forthe transesterification or amidation reaction. Any of the catalystsconventionally useful for these reactions may be used, provided it doesnot stop the subsequent crosslinking of the polymer. For instance, knowntransesterification catalysts such as alkyl titanates, zinc acetate,alkali metal alkoxides, dibutyltin dilaurate, stannous octoate,butylstannoic acid, and (other) Ti, Sn, Zn, Mn and Pb compounds may beused. Some compounds such alkali metal alkoxides (see U.S. Pat. No.5,656,692 for the use of this type of transesterification catalyst) mayslow the crosslinking reaction. Preferred catalysts are tetralkyltitanates such as tetrabutyl titanate, and dibutyltin dilaurate. Typicalamounts of catalyst may be used, for example 0.03 to 5 weight percent ofthe first polymer, more typically 0.1 to 2 weight percent of the firstpolymer. The catalyst may be dissolved in a small amount of an inertliquid compound or a portion of the olefinically unsaturated compound inorder to mix it with the first polymer. Inert liquids include aromatichydrocarbons such as xylene, 1,2,3,4-tetramethylbenzene, and isodurene,and chlorinated hydrocarbons such as o-dichlorobenzene. The use of thesecatalysts often reduces the temperatures and/or times required for thereaction to take place.

Since the transesterification reactions are equilibrium reactions todrive them to completion it may be preferable to remove the byproductalcohol R²OH from the reaction. This can be done by allowing this(usually volatile) alcohol to volatilize. Vacuum may be applied and/oran inert gas sweep used to help remove this byproduct. An inert gasatmosphere may also help prevent discoloration and/or other degradationduring the reaction.

The transesterification/amidation may be carried out in a variety ofways. To ensure complete mixing of the alcohol and/or amine and thefirst polymer all of these materials (and catalyst if present) may bedissolved in a solvent and the byproduct alcohol distilled from thesolution. While this may be a good way of ensuring uniform reaction,dissolution of polymers and their recovery from solution is often anexpensive process, so other methods may be desirable. One method is toheat the polymer while mixing it (at a temperature above its meltingpoint and/or Tg, if any) in a polymer mixing apparatus. While thepolymer is being kneaded by the mixer the alcohol and/or amine (andcatalyst if used) may be added, and the mixing continued until thedesired degree of reaction is achieved.

A more preferred method is a continuous process in which the firstpolymer, alcohol and/or amine, and catalyst (if present) are fed to,heated, mixed, and allowed to react in a single or twin screw extruderor similar apparatus. The screw configuration is preferably chosen touniformly mix the various ingredients to ensure that a uniform secondpolymer is produced, and has one or more reaction zones that preferablyretard the loss of unreacted olefinically unsaturated compound(s). Thetemperature and residence time in the extruder are such that the desireddegree of reaction is obtained. In the extruder, vacuum sections orports may be used to remove the byproduct alcohol R²OH, and may also beused to remove unreacted olefinically unsaturated alcohol and/or primaryamine from the product polymer at the exit end of the extruder. Typicalresidence times in an extruder are about 20 sec. to about 5 min,preferably 1 to 2 min, with additional residence time up to about 20 min(if desired) in heated pipes and/or melt pumps.

The second polymer is then cured using a conventional sulfur or peroxidecure for unsaturated (olefinic) polymers. The first polymer (beforereaction) and/or the second polymer may contain other ingredientsnormally present in thermoplastics or elastomers, so long as they do notinterfere with the amidation/transesterification if present in the firstpolymer or the curing if present in the second polymer. For example,large amounts of oils are usually not present when peroxide cures areemployed, since they often slow down and/or interfere with the cure.These materials may include fillers/reinforcing agents such as carbonblack, clay, talc, glass fiber and silica, pigments or coloring agentssuch as calcium sulfate and TiO₂, antioxidants, antioxonants, oils,plasticizers, release agents, etc. Peroxide cures often employ coagentssuch as triallyl iscyanurate or “HVA-2” (m-phenylene-bis-maleimide),trimethylolpropane trimethacrylate, trimethylolpropane acrylate, andtriallyl cyanurate to speed the cure and/or improve the properties ofthe vulcanizate.

The crosslinked polymer produced by the process described herein isnovel. Also novel are compositions containing the second polymer and asulfur cure system or a peroxide cure system.

Blends of the first polymer and the second polymer may also be made andthen cured using a sulfur or peroxide curing system, preferably aperoxide curing system. It is preferred that in such blends the secondpolymer is at least about 20 weight percent of the polymer present,based on the total amount of first and second polymers present.Surprisingly, even with the blend containing less of the olefinicunsaturated containing component, the polymers still cure rapidly andgive vulcanizates with good properties.

Vulcanizates of the second polymer have good properties, but, similar tothe product of all curing reactions these properties may vary dependingon the cure used and the starting polymer composition. A good test forthe stability of the crosslinks form is compression set at a giventemperature. In this type of a test a (usually cured) polymer part issubjected to compression stress while being heated to a certaintemperature. After a given period of time the stress is released, andthe part cooled. The amount of the strain that the part does not recoveris the compression set, and the lower the number the more stable thecrosslinks are to rearrangement or simply being destroyed. This test isparticularly important for parts that are to be used under compression,such as seals and gaskets.

It has been found that aside from the particular curing system used, theproportion of unreacted olefinically unsaturated alcohol and/or primaryamine remaining in the second polymer and the absolute amount of reacted(present as side chains) olefinically unsaturated alcohol and/or primaryamine present in the second polymer greatly affect the compression set.When the molar percentage (based on the total number of “moles” ofreacted and unreacted olefinically unsaturated alcohol and primary aminepresent) of reacted olefinically unsaturated alcohol and primary aminepresent is relatively high the compression set is greatly improved(lower). Thus it is preferred that the second polymer contain more thanabout 70 mole percent, more preferably more than about 80 mole percent,especially preferably more than about 90 mole percent of reactedolefinically unsaturated alcohol and primary amine. This high level ofreacted olefinically unsaturated alcohol and/or primary amine can beachieved by reacting most of the added alcohol and/or amine, and/orremoving unreacted alcohol and/or amine. The latter can be done forexample by subjecting the molten polymer to a vacuum, for instance avacuum section in an extruder. These trends are illustrated in Examples12-19 herein. For instance, in Example 12 there is only 6 mole percentof ungrafted alcohol in the polymer and the compression set is 73%,while in Example 15 there is 20 mole percent of ungrafted alcohol andthe compression set is 80%. The proportions of reacted and unreactedalcohol and/or amine can be determined by NMR spectroscopy (see below).

It has also been found that if the first polymer is dried before beingreacted with the olefinically unsaturated alcohol and/or amine that theamount of unreacted alcohol and/or amine in the second polymer isreduced. It is therefore preferred to dry the first polymer before thisreaction. Before drying, the polymer may contain about 0.2 to 0.8%water. The polymer can be dried in a vacuum oven: overnight drying at80° C., with a vacuum and slow nitrogen purge, can reduce the watercontent to about 0.01%, which can rise to about 0.05% after exposure toambient conditions for a day or two. The polymer can also be dried bypassing it through an extruder, without any other ingredients, whilepulling a vacuum on vent ports placed over two or more of the extruderzones. The screw can be run at 200-250 rpm or any convenient speed, andthe temperature profile adjusted so that the polymer's exit temperatureis about 200° C. Under these conditions, the moisture content can bereduced to about 0.01-0.02%. The drying may also be accomplished at theback (feed) end of the extruder before introduction of the olefinicallyunsaturated compound and catalyst (if used). After heating the polymerin the first few zones of the extruder, the moisture is removed at avent port, followed by a melt seal designed to separate the dryingprocess from the transesterification or transamidation taking place inthe next zones of the extruder. The melt seal can consist of a blisterring or reverse elements incorporated into the extruder screws.

In order to achieve good (low) compression set it has been found that aminimum level of reacted olefinically unsaturated alcohol and/or primaryamine should be present in the second polymer. This is especially truewhen a sulfur cure system is used. Preferably there should be 30mmol/100 g of second polymer or more, more preferably about 35 mmol/100g of second polymer or more, of reacted olefinically unsaturated alcoholand/or primary amine present. A combination of low unreactedolefinically unsaturated alcohol and/or primary amine, and the minimumpreferred amount of reacted olefinically unsaturated alcohol and/orprimary amine often leads to the best (lowest) compression sets and/orfast cure rate.

In another preferred composition of the second polymer it is preferredthat at least about 0.5 mole percent, preferably at least about 1.0 molepercent, and especially preferably at least about 2.0 mole percent of R²contain olefinic unsaturation.

In the Examples the following methods were used to test the polymercompositions.

Property or Test ASTM # Specific Conditions Mooney Viscosity D1646 LargeRotor; 100 C; 1 min preheat; 4 min test Oscillating Disk D2084 MonsantoODR; Small Rotor; Rheometer 1 deg arc Rotorless Curemeter D5289 AlphaTechnologies MDR-2000; 0.5 deg arc Stress/Strain Properties D412 Die CDumbbell Hardness D2240 Durometer Type A Compression Set D395 Method BTear D624 Die C Specimen

In the examples, except for Examples 12-19 in which Henkel® 3317 orHenkel® 3318 were used, ¹H nmr spectra were measured with a 300 MHz GEspectrometer, in CDCl₃ as solvent, with tetramethylsilane as an internalstandard. For the NMR analysis, the areas under peaks assigned to theunsaturated alcohol were compared with those under peaks assigned to theMA units of the E/MA. The relevant proton resonances for the MA unitsappeared at δ3.65 ppm (pendant CH₃O moiety) and δ2.3 ppm (CHCOO moiety).Protons that resulted from the grafting of undecylenyl alcohol (forother alcohols analogous peaks and corrections would be used) appear atδ4.05 ppm (CH₂OCO moiety linked to the polymer backbone). The vinylCH₂═C protons at δ5.0 ppm belonged to the unsaturated alcohol, bothbefore and after grafting. To determine the initial MA content from the3.65 ppm peak, a correction was applied for loss of CH₃O duringreaction: in the absence of side-reaction, the loss at 3.65 ppm wasequal to 1.5 times the peak that appeared at 4.05 ppm. Unless otherwiseindicated, the average mole ratios of the attached ω-undecylenyl alcoholto initial MA was a direct average of the 4 ratios calculated bycomparing the 5.0 ppm and 4.05 ppm peaks with the 2.3 ppm and corrected3.65 ppm peaks. Similar methods would apply to using unsaturated amines.

Because the NMR peak areas suggested that there are slightly fewerprotons at δ5.0 ppm than at δ4.05 ppm, there appeared to be little or nounreacted undecylenyl alcohol remaining in the products. In Examples1-11, the alcohol may have been volatile enough to be driven off duringthe reaction and/or removed during polymer purification.

All reagents were used as received. ω-Undecylenyl alcohol(10-undecen-1-ol, 99%), titanium n-butoxide, 1,2,3,5-tetramethylbenzeneand 1,2,3,4-tetra-methylbenzene were obtained from the Aldrich ChemicalCompany. o-Dichloro-benzene, methylene chloride (CH₂Cl₂), and methanolwere obtained from EM Science. Isodurene (˜90%) and, for the extruderexperiment, 10-undecen-1-ol (˜96%) were obtained from the Fluka ChemicalCorporation. Poly(ethylene-co-methyl acrylate) dipolymers were obtainedfrom the DuPont Company. The dipolymer with 62 wt % methyl acrylate (MA)and a melt index (190° C.) of about 25-40 g/10 min is designated E/62MAand another with 59 wt % MA and a melt index of ˜8 is designated E/59MA.These copolymers can be made by methods described in U.S. Pat. Nos.3,904,588 and 5,028,674.

In the Examples, the following abbreviations are used:

E—ethylene

E_(B)—elongation (%) at break

M₁₀₀—stress required to elongate specimen 100% (2 times original lengthof bench mark on dumbbell)

m/m—mol/mol (mole ratio)

MA—methyl acrylate

MDR—Rotorless Curemeter

ODR—Oscillating Disk Rheometer

ROH—olefinically unsaturated alcohol

T_(B)—tensile strength at break

EXAMPLES 1-6 Equipment and Materials

Melt reactions were conducted batchwise in a Brabender Plasticorder®(C.W. Brabender Instruments, Inc., South Hackensack, N.J., U.S.A.) witha Type 6 Mixer/Measuring Head with roller blades (˜60 ml cavity).Scale-up runs were also performed in a Brabender Plasticorder® equippedwith a 3-piece Prep Mixer® and roller blades (˜350 ml cavity). Thetypical total charge for the Type 6 was 50 g and for the larger mixer,250 g. Continuous melt reactions were conducted in a twin-screw extruderdescribed more completely in one of the examples.

Example 1 Grafting ω-Undecylenyl Alcohol Onto E/62MA at 200° C.

To a Type 6 Brabender mixer/measuring head at 200° C. and under nitrogenblanket, with roller blades turning at 75 rpm, were charged 45.0 g ofE/62MA and 5.9 ml ω-undecylenyl alcohol (5.0 g at reported density,calculated mole ratio of ROH/MA=9.1%). After 2 min of mixing, 0.32 ml of25% (w/w) titanium tetra-n-butoxide in o-dichlorobenzene (catalystsolution) was added gradually by syringe to the clear melt. Followingcatalyst addition, the Brabender torque rose gradually from 110 to 260m-g. The mixer blades were stopped, the head disassembled, and theproduct discharged 13 min after beginning the catalyst addition. Part ofthe product (10.0 g) was dissolved in 50 ml of CH₂Cl₂, the solutionprecipitated in 250 ml of methanol in a blender. The precipitated solidwas rinsed three times with 100-ml portions of methanol, each timekneaded in the presence of the liquid to improve extraction ofimpurities, and, after decanting, squeezed to expel the maximum possibleliquid. The solid was dried overnight on polytetrafluoro-ethylenesheeting in the fume hood and then at RT in a vacuum oven for 24 h undervacuum and with nitrogen bleed. From this precipitated solid, 1 g wasredissolved in 5 ml of CH₂Cl₂ and reprecipitated in 25 ml of methanol ina stirred beaker. The above rinsing and decanting procedure wasrepeated, and the solid also dried as above. Samples were analyzed by ¹HNMR, designated 1-A (unpurified), 1-B (precipitated), and 1-C(reprecipitated). The analysis showed that the average fraction ofmethyl acrylate (MA) replaced by ω-undecylenyl alcohol was 5.9 (1-A),5.4 (1-B), and 5.4% (1-C). This value was the mole ratio of attachedalcohol to initial MA.

Example 2 Grafting ω-Undecylenyl Alcohol Onto E/62MA at 230° C.

The procedure of Example 1 was repeated except that the Brabender washeated to 230° C. Following catalyst addition, the Brabender torque roserapidly from 50 to 330 m-g and then leveled off at 280 m-g. The averagefraction of MA replaced by ω-undecylenyl alcohol was 6.3 (2-A), 5.8(2-B), and 5.7% (2-C).

Example 3 Grafting ω-Undecylenyl Alcohol Onto E/62MA

To a Type 6 Brabender mixer/measuring head at 200° C. and under nitrogenblanket, with roller blades turning at 75 rpm, were charged 45.0 g ofE/62MA and 5.9 ml ω-undecylenyl alcohol (5.0 g at reported density,calculated mole ratio of ROH/MA=9.1%). After 2 min of mixing, 0.42 ml of25% (w/w) titanium tetra-n-butoxide in isodurene (catalyst solution) wasadded gradually by syringe to the clear melt. Following catalystaddition, the Brabender torque rose gradually from 80 to 170 m-g. Themixer blades were stopped, the head disassembled, and the productdischarged 13 min after beginning the catalyst addition. Part of theproduct (5.0 g) was dissolved in 25 ml of CH₂Cl₂, the solutionprecipitated in 150 ml of methanol in a blender. The precipitated solidwas rinsed three times with 50-ml portions of methanol, each timekneaded in the presence of the liquid to improve extraction ofimpurities, and, after decanting, squeezed to expel the maximum possibleliquid. The solid was dried overnight on polytetrafluoro-ethylenesheeting in the fume hood and then at RT in a vacuum oven for 24 h undervacuum and with nitrogen bleed. The purified product was analyzed by ¹HNMR, which showed that the average fraction of MA replaced byω-undecylenyl alcohol was 6.4%.

Examples 4-6 Grafting ω-Undecylenyl Alcohol Onto E/62MA

To a Brabender Plasticorder® equipped with a 3-piece Prep Mixer® androller blades at 200° C. and under nitrogen blanket, with roller bladesturning at reduced speed were charged the E/MA and alcohol indicated inTable 1 (alcohol/MA=9.1 mol %). The speed of the roller blades wasincreased to 75 rpm. Because the temperature of the Brabender andcontents fell during the charging of ingredients, mixing was allowed tocontinue until the temperature again rose to 200° C., in about 8-13 min.With the reactants at 200° C., 25% (w/w) titanium tetra-n-butoxide in1,2,3,4-tetramethylbenzene (the catalyst solution indicated in Table 1)was added gradually, and the mixing was allowed to continue for anadditional 13 min. Then the mixer blades were stopped, the headdisassembled, and the product discharged. NMR analysis of the productindicated the average fraction of MA replaced by ω-undecylenyl alcohol,shown in Table 1.

TABLE 1 Example 4 5 6 E/62MA, g 225 225 — E/59MA, g — — 225ω-undecylenyl alcohol, g 25.1 25.0 24.1 Catalyst Solution, ml 2.1 2.11.1 C = C/original MA (m/m), 7.2% 6.2% 9.4% (δ5.0 vs. 3.65 & 2.3 ppm)Grafted ROH/original MA (m/m), 8.4% 6.6% 8.3% (δ4.05 vs. 3.65 & 2.3 ppm)Overall average % MA replaced by alcohol 7.8% 6.4% 8.8%

The products obtained above, with pendant unsaturation, were compoundedon a rubber mill and successfully cured with a sulfur-compound-basedrecipe. Compared with a similar polymer, composed of ethylene, methylacrylate, and monoethyl maleate and cured with a diamine, thesulfur-cured polymers offered greater resistance to premature reaction(“scorch”) and much faster cure. Tear strength was enhanced incomparison with a peroxide-cured ethylene-methyl acrylate dipolymer ofvery similar composition (Comparative Example A), as shown in Table 2.Curing and physical properties are summarized in Table 2. By 5/6 ismeant a mixture of polymers from Examples 5 and 6.

TABLE 2 Example A 4 5/6 6 E/62MA 100 — — — Polymer from Example 4 — 100— — Polymer from Example 5 — — 85 — Polymer from Example 6 — — 15 100Cure-system, type peroxide^(a) sulfur^(b) sulfur^(c,d) Sulfur^(b,d) C =C cure-site ˜47 ˜45 ˜58 concentration mmol/ mmol/ mmol/ 100 g 100 g 100g ODR, 30 min @ 160 C. — 4.8 4.7 5.6 Torque maximum, N · m Torque,minimum, N · m 0 0.15 tc90, minutes 12.4 9.7 Hardness, Shore A 60 66 6771 Tensile properties M₁₀₀ (MPa) 4.6 5.4 5.2 6.2 T_(B) (MPa) 13.1 14.415.0 15.9 E_(B) (%) 197 240 240 230 Tear strength (kN/m) 25 32 — —Compression set, 22 88 66 82 70 hr @ 150° C. (%) Compression set afterpost- — 50 52 cure, 70 hr @ 150° C. (%) ^(a)Rubber compound: elastomer(100), stearic acid (1.5), Naugard ® 445 (1), Vanfre ® VAM (0.5), SRFcarbon black (60), Vulcup ® R (3.2), HVA-2 (2). Press Cure only: 20min@177° C. ^(b)Rubber compound: elastomer (100), zinc oxide (5),stearic acid (1), Naugard ® 445 (1), SRF Black (60), sulfur (1.5), MBT(0.5), Thionex ® (1.5). Press Cure only: 20 min @ 160° C. ^(c)Rubbercompound: elastomer (100), zinc oxide (5), stearic acid (1), Naugard ®445 (1), SRF Black (60), sulfur (0.5), Thionex ® (1), Methyl Zimate (3),Butyl Zimate (3), Sulfasan ® R (1), TMTD (2.5). Press Cure: 20 min @160° C. ^(d)One group of compression set pellets oven post-cured 4 hrs @160° C.

Examples 7-11 Continuous Extruder Graftin ω-Undecylenyl Alcohol OntoE/62MA

The following equipment was used for these Examples

(a) A 5.1 cm (2″) satellite single-screw extruder to feed E/MAelastomer.

(b) Berstorff® (Florence, Ky., U.S.A.) ZE-25 twin screw extruder, 25 mmdiameter, L/D=38, co-rotating, intermeshing. A hard working screw designwas employed, including blister rings, kneading, mixing and reverseelements. These elements created regions of hold-up (melt seals) atseveral places along the screw.

(c) two ISCO® (ISCO Inc., Lincoln, Nebr., U.S.A.) digital syringe pumps,model 500D, to feed ω-undecylenyl alcohol and catalyst solution

(d) Nash water ring vacuum pump, Model MVF15

(e) refrigerated cold trap working at −60° C.

The following materials were used:

E/62MA E. I. du Pont de Nemours and Company Wilmington, DE U.S.A.10-undecen-1-ol Supplier: Fluka (ω-undecylenyl alcohol) Assay: 96%titanium (IV) butoxide Supplier: Aldrich Assay: 99% 1,2,3,5-tetramethylbenzene Supplier: Aldrich Assay: 80%

The E/MA polymer was fed at a controlled rate into the Berstorffextruder, the polymer at a temperature of about 100° C. at the point ofinjection into the Berstorff, Zone 0. The Berstorff extruder consistedof 7 zones, all heated at the same temperature specified in Table 3, andan eighth zone (the die) set at 200° C. The ω-undecylenyl alcohol wasmetered out by syringe pump and fed into zone 1 (at the input end) ofthe Berstorff extruder. Each day, a fresh batch of catalyst solution(25% w/w titanium [IV] n-butoxide in 1,2,3,5-tetramethylbenzene) wasprepared and put into the ISCO syringe pump for delivery either to Zone1 or Zone 4 of the Berstorff. A vent port was located at Zone 6. After asteady-state throughput was achieved, and prior to injecting alcohol andcatalyst, the E/MA polymer flow-rate was checked by weighing the outputof polymer over a 2-minute interval. The polymer exiting the die wascollected in tared polytetrafluoroethylene-lined fry pans over measuredtime intervals (usually 2 min), cooled in a trough of cooling water, andweighed to determine product output rate. Occasionally throughout theexperiment, polymer throughput was determined gravimetrically with theliquid streams turned off. By-product methanol and some of the unreactedω-undecylenyl alcohol were removed near the output end of the Berstorffat a vacuum port on the extruder connected to the vacuum pump and coldtrap described above.

The target throughput for E/MA was 60 g/min, which was measured prior tothe introduction of liquids. At the end of the Examples an output of58.7 g/min was measured, with the alcohol stream shut off. The residencetime was about 1.2-1.5 min. This output was almost entirely E/MA,because of the low level of added catalyst and the volatility of thecatalyst carrier solvent, which should ensure its removal at the vacuumport. The ω-undecylenyl alcohol was fed in at a rate of 7.86 ml/min. TheBerstorff extruder screw speed was 205 rpm. Catalyst flow-rate andBerstorff barrel temperature were varied in the manner described inTable 3.

To calculate the average fraction of MA replaced by ω-undecylenylalcohol, NMR analysis was performed in the manner described previously,but without using the vinyl proton peak at δ5.0 ppm. A base-linecorrection was applied to the product peak area at 4.05 ppm, bysubtracting the corresponding area in the spectrum of a sample for whichreaction did not appear to occur. The base-line corrected analysis isgiven in Table 3. In Table 4, the data is reported with and withoutapplication of the base-line correction. No correction was applied tothe data reported for the blend in the first column of Table 4, which isequal to the sum of 85% of the grafted/original MA of Example 5 and 15%of the grafted/original MA of Example 6.

TABLE 3 Example 7 8 9 10 11 Set temperature, Zones 220° C. 240° C. 240°C. 220° C. 240° C. 1-7 Catalyst injection zone 1 1 4 4 4 Catalyst feed(ml/min) 3.6 3.6 1.2 3.6 1.5 Total output (g/min) 66.5 66 62.5 60 ˜66Extruder amps 5 5 5 5 — Discharge pressure 350 550 590 690 660 (kPa)Average fraction of 1.0% 2.4% 1.8% 2.4% 1.6% MA replaced byω-undecylenyl alcohol, with baseline correction

The products obtained from extruder-grafting of ω-undecylenyl alcohol,above, were compounded on a rubber mill with a sulfur-type curing recipeand vulcanized, the vulcanizate physical properties shown in Table 4.Except for the sample containing the fewest pendant vinyl groups, alltested samples could be sulfur-cured. Because their unsaturation levelwas lower than the grafts prepared in the Brabender Plasticorder®, theycured more slowly and gave a looser cross-link network, as evidenced bylower modulus, higher elongation at break, and higher compression set.The data demonstrates a good correlation between degree of unsaturationand both cure and physical properties.

TABLE 4 5 (85%) + Polymer of Example 6 (15%)^(b,c) 8^(a,c) 9^(a,c)11^(a,c) 7^(a,c) C═C cure-site concentration, ˜45 ˜17 ˜14 ˜12 ˜7mmol/100 g Average fraction of MA replaced by ω-undecylenyl alcohol,NMR, noise-corrected 2.4% 1.8% 1.6% 1.0% NMR, not noise-corrected 6.9%2.9 2.4 2.1% 1.4% Cure-rate: ODR, 30 min @ 160° C. torque minimum, N m0.15 0.11 0.11 0.11 0.08 t_(s2), minutes 4.0 5.3 8.6 8.4 — torquemaximum, N m 4.7 2.5 1.3 1.5 0.18 t_(c)90, minutes 9.7 10.1 11.7 11.8 NoCure Hardness, Shore A 67 66 62 64 No cure Tensile properties, originalM₁₀₀ (MPa) 5.2 4.8 3.3 3.3 No cure T_(B) (MPa) 15.0 15.0 13.1 13.5 Nocure E_(B) (%) 240 322 432 428 No cure Heat-aged 2 wk @ 150° C. M₁₀₀(MPa) — 16.4 12.8 13.0 No cure T_(B) (MPa) 17.0 19.4 16.6 16.2 No cureE_(B) (%) 98 138 159 142 No cure Compression set, 50 89 92 93 No cure 70hr @ 150° C. (% set) ^(a)Press Cure: 20 min @ 160° C.; post-cure @ 160°C.: 4.5 hrs for slabs, 4 hrs for compression set pellets ^(b)Press Cure:20 min @ 160° C.; post-cure for compression set pellets: 4 hrs @ 160° C.^(c)Rubber compound: elastomer (100), zinc oxide (5), stearic acid (1),Naugard ® 445 (1), SRF Black (60), Methyl Zimate (3), Butyl Zimate (3),Sulfasan ® R (1), sulfur (0.5), Thionex ® (1), TMTD (2.5).

Some of the products obtained from extruder-grafting of ω-undecylenylalcohol, above, were compounded on a rubber mill with a peroxide-typecuring recipe and vulcanized; the vulcanizate physical properties areshown in Table 5. As shown by the ODR data, the unsaturation graftedonto the E/MA led to faster peroxide vulcanization than the dipolymercontrol which contains no unsaturation. The grafted E/MA also attained ahigher state of cure as shown by the final ODR torque when curing wascomplete. Vulcanizate compression set resistance of the grafted E/MA wasalso improved relative to the control.

Curing conditions are the same for compound in Tables 5 and 6,compression molding for slabs and pellets—15 min at 177° C., and ovenpost cure for one group of compression set pellets—4 at 177° C.

TABLE 5^(a) E/62MA Dipolymer^(b) 100.0 — — 50.0 Polymer from Example 10— 100.0 — — Polymer from Example 11 100.0 50.0 Mooney Viscosity, 100°C., ML-4 11.6 11.0 10.9 11.4 ODR Cure, 177° C., Torque, dNm 2.5 min 1.914.7 7.1 4.4   5 min 4.6 41.8 27.5 16.3  10 min 8.0 58.9 43.2 27.2  20min 9.5 63.3 47.8 31.0  30 min 9.5 63.6 48.4 31.4 Maximum Cure rate,dNm/min 1.1 13.6 9.0 5.0 Stress-strain,^(c) original, 25° C. 100%modulus, Mpa 2.2 13.0 9.3 5.6 Tensile strength at break, MPa 10.2 14.614.3 13.7 Elongation at break 430%  107%  136%  189%  ShoreHardness,^(c) A 68 71 75 72 Compression set, method B, 70 hr/150° C.Press cure (15 min/177° C.) 45% 21% 30% 31% Press + post-cure (4 hr/177°C.) 30% 11% 14% 14% ^(a)Compound contains (by wt): elastomers (100.0),Vanfre ® VAM (0.5), Armeen ® 18D (0.5), stearic acid (1.5), Naugard ®445 (1.0), SRF Black, N-774 (65.0), TP-759 (5.0), Vulcup ® R (2.5),HVA-2 (1.0) ^(b)Nominal melt index = 40 ^(c)Samples press cured 15 minat 177° C.

Surprisingly, it is found that the substantial improvement in set isretained even in compounds that are based on blends of polymer graftedwith unsaturation and virgin polymer that contains no graftedunsaturation, shown in Table 6. This is also shown by the last column inTable 5.

TABLE 6^(a) E/62MA Dipolymer^(b) 100.0 — 50.0 62.5 75.0 Polymer ofExample 11 — 100 50.0 37.5 25.0 Average fraction of MA 0  1.6%   1.6%  1.6%   1.6%  replaced by ω-undecylenyl alcohol, with baselinecorrection Mooney Viscosity, 100° C., 10.7 10.9 12.1 13.0 17.4 ML-4 ODRCure, 177° C. Torque, dNm 2.5 min 3.4 7.1 7.3 6.8 4.5 5 min 8.7 27.520.8 18.0 14.7 10 min 12.9 43.2 31.1 26.6 22.4 20 min 14.1 47.8 33.929.3 24.9 30 min 14.0 48.4 34.2 29.4 24.9 Stress-strain^(c), original,25° C. 100% modulus, MPa 1.8 9.3 5.1 4.5 3.5 200% modulus, MPa 4.5 —14.9 12.6 9.8 Tensile strength at break, 10.4 14.3 14.5 13.2 12.3 MPaElongation at break 442% 136% 199% 208% 243% Shore Hardness^(c), A 66 7571 63 64 Compression set, method B, 70 hr/150° C. Press cure (15min/177° C.)  48%  30%  32%  29%  41% Press + post-cure  30%  14%  14% 16%  14% (4 hr/177° C.) ^(a)Compound contains (by wt): elastomers(100.0), Vanfre ® VAM (0.5), Armeen ® 18D (0.5), stearic acid (1.5),Naugard ® 445 (1.0), SRF Black, N-774 (65.0), TP-759 (5.0), Vulcup ® R(2.5), HVA-2 (1.0) ^(b)Nominal melt index = 40 ^(c)Samples press cured15 min at 177° C.

Examples 12-19 Continuous Extruder Grafting of Commercial Oleyl AlcoholOnto E/62MA

The procedure described in Examples 7-11 was followed except that acommercial grade of oleyl alcohol was used as grafting agent in place ofω-undecylenyl alcohol. The oleyl alcohol, obtained from the HenkelCorporation and known as Henkel® 3317 or HD Ocenol® 90/95, wasapproximately 90% pure, the balance being saturated long-chain alcohols.The zones were defined differently in these examples, with the polymerfeed zone designated ‘1’ instead of the ‘0’ reported in previousexamples. Thus, the polymer was fed to zone 1, the alcohol to zone 2,and the catalyst solution to the zone specified in Table 7. The ventport was at zone 7.

The target throughput for E/62MA was 60 g/ min, which was measured priorto the introduction of liquids, and found to be 62-65 g/min at variouspoints during the run. The Henkel® 3317 was fed in at a rate of 12.6ml/min. Extruder screw speed was 190-200 rpm. Catalyst flow-rate andBerstorff barrel temperature were varied in the manner described inTable 7. Example 15 differed from the rest in that the catalystconsisted of a 12.3% (w/w) solution of titanium [IV] n-butoxide inHenkel® 3317, fed at 4.8 ml/min, and the separate Henkel® 3317 alcoholfeed was reduced to 8.3 ml/min (to mix approximately the same amount ofunsaturated alcohol into E/62MA as in the other examples). Since thecommercial alcohol contained 90% oleyl alcohol, its only unsaturatedconstituent, the amount of MA replaced by unsaturated alcohol wascalculated to be 90% of the total amount of MA replaced by Henkel® 3317,as shown in Table 7. Because the long-chain alcohols were relativelynon-volatile, some were retained in the polymer even if not grafted.

The fraction of MA replaced by Henkel® 3317 and ratio of grafted tototal alcohol in the product that are reported in Table 7 were obtainedfrom the proton NMR data and calculations given in Table 8. The NMRspectra were measured with a 400 MHz spectrometer (Bruker AM-400). Themol % of all the alcohol in the sample, relative to MA (Column F), wascalculated from the vinyl protons at δ5.3 ppm (that represent thegrafted and ungrafted unsaturated alcohol in the sample) and the methineprotons at δ2.3 ppm (that represents the starting MA content of theE/62MA). Because NMR analysis had shown that Henkel® 3317 contained 90%unsaturated oleyl alcohol, a correction factor was applied to determinethe total alcohol content, both saturated and unsaturated. Instead ofdividing the peak area of column B by 2 to obtain the relative number ofmoles of total alcohol, it was divided by 2×0.90=1.8. NMR analysis hadalso shown that some of MA's methine proton had been consumed during themanufacture of E/62MA—the peak area at δ2.3 ppm measured 0.92, insteadof 1.00, relative to the 3.0 for MA's methyl ester peak at δ3.6 ppm.Therefore a second correction was applied, dividing the peak area ofcolumn E by 0.92 rather than 1.00 to obtain the relative number of molesof MA prior to the reaction. Thus, the mol % of all the alcohol in thesample, relative to MA (Column F), was (100%×Column B/1.8)/(ColumnE/0.92).

The fraction of MA replaced by all the alcohols in Henkel® 3317 (ColumnG) was determined by comparing the CH₂ ester protons that resulted fromthe grafting of the alcohol, at δ4.0 ppm, with MA's CH₃ ester peaks atδ3.6 ppm. To determine the initial MA content from the δ3.6 ppm peak, acorrection was applied for loss of CH₃ during the transesterificationreaction, which is equal to 1.5 times the number of CH₂ ester protonscreated. Thus, the mol % of replaced MA (Column G) was (100%×ColumnC/2)/(Column C×1.5/3+Column D/3). The fraction of MA replaced by all thealcohols in Henkel® 3317 in Column H was determined by a second method,comparing the CH₂ ester protons that resulted from the grafting of thealcohol, at δ4.0 ppm, with MA's CH peak at δ2.3 ppm. The same correctionwas applied for the loss of CH during manufacture of E/62MA, asdescribed above. Thus, the mol % of replaced MA (Column H) was(100%×Column C/2)/(Column E/0.92). The ratio of grafted/total alcohol inthe extruder product (Column I) was determined by comparing the fractionof MA replaced by alcohol with the amount of total alcohol relative toMA. Thus, this ratio was (100%×Column H/Column F).

TABLE 7 Example 12 13 14 15 Set temperature, Zones 1-7 260° C. 240° C.260° C. 260° C. Catalyst injection zone 3 5 5 3 Catalyst feed (ml/min)2.4 2.4 2.4 4.8 Total output (g/min) 74.0 72.5 69.0 72.5 Extruder amps5.5 5.5 5.5 5.5 Discharge pressure (kPa) 350-410 480 480-690 280 Averagefraction of MA 5.6% 6.0% 6.7% 6.4% replaced by Henkel ® 3317 (grafted)Average fraction of MA 5.0% 5.4% 6.1% 5.8% replaced by unsaturatedalcohol component of Henkel ® 3317 (grafted) Grafted/total alcohol in 94%  90%  93%  84% sample

TABLE 8 Column G Column H Column B Column C Column F Fraction FractionColumn I Total Grafted Column D Total of MA of MA Grafted Henkel ® 3317Henkel ® 3317 MA (ester Column E Henkel ® replaced by replaced by TotalHenkel ® Column A (vinyl (ester CH₃ MA (CH 3317/MA, mol Henkel ® 3317Henkel ® 3317 3317 Example protons) CH₂ protons) protons) proton) %(grafted), 1 (grafted), 2 in sample CH₂ = CH₂OC CH₃OC CH δ5.3 ppm* δ4.0ppm* δ3.6 ppm* δ2.3 ppm* PEAK AREAS 12 789 823 21134 6622 6.09 5.52 5.7293.9 13 829 831 19545 6319 6.71 6.00 6.05 90.2 14 1038 1077 22485 72867.28 6.70 6.80 93.4 15 872 809 17888 5763 7.73 6.35 6.46 83.5 *Peakposition, relative to tetramethylsilane at 0 ppm.

Additional graft materials were prepared in the same extruder in asimilar manner, using Henkel® 3317 or 3318 as grafting agents. Henkel®3318, also known as HD Ocenol® 110/130 is another unsaturated alcoholthat contains about 35% linoleyl alcohol, 10% linolenyl alcohol, and 40%oleyl alcohol, the balance made up of saturated long-chain alcohols. Thegrafting results are given in Table 9. Since Henkel® 3317 or 3318contains 85% unsaturated alcohols, the amount of MA replaced byunsaturated alcohols was calculated to be 85% of the total amount of MAreplaced by Henkel® 3318, as shown in Table 9.

TABLE 9 Example 16 17 18 19 Alcohol grafting agent Henkel ® Henkel ®Henkel ® Henkel ® 3317 3317 3318 3318 Average fraction of MA 6.8%  6.0%6.0% 6.5% replaced by Henkel ® 3317 or 3318 Average fraction of MA 6.1% 5.4% 5.1% 5.5% replaced by unsaturated alcohol component of Henkel ®3317 or 3318 Grafted/total alcohol in  92% 87  82%  78% sample

The grafted polymers from Tables 7 and 9 were vulcanized with a sulfurcure system, and selected curing and physical properties shown in Table10.

TABLE 10^(a,b) Polymer of Example 12 13 14 15 16 17 18 19 MDR, 30 min @160° C. Torque, minimum, Nm 0.05 0.02 0.02 0.02 0.02 0.02 0.02 0.02Torque, maximum, Nm 1.34 1.50 1.38 1.29 1.56 1.25 1.03 1.18 Tc90,minutes:seconds 7:18 7:31 7:35 7:50 7:41 8:01 8:12 8:87 Hardness, ShoreA 61 62.5 60.5 59 62.5 61.0 62.5 60.0 Tensile strength at break, 12.412.0 13.0 11.3 13.4 12.1 14.4 13.3 Mpa Elongation at break, % 277 247237 253 267 287 347 270 Compression Set, % 70 hours/150° C.^(c) 73.369.7 72.9 80.2 69.1 77.6 80.6 81.7 Tear Strength, Die C, 125° C. N/mm7.35 7.71 9.46 8.76 9.28 9.81 11.73 10.33 ^(a)Sulfur curing recipe:elastomer (100), zinc oxide (5), stearic acid (1), Naugard ® 445 (1),SRF Black (60), Methyl Zimate (3), Butyl Zimate (3), Sulfasan ® R (1),sulfur (0.5), Thionex ® (1), TMTD (2.5). ^(b)Press Cure: 20 minutes @160° C.; Oven Post Cure: 4 hours @ 160° C. ^(c)Test conditions forCompression Set

What is claimed is:
 1. A process for crosslinking a polymer, comprising:(a) transesterifying or amidating a first polymer consisting essentiallyof about 10 or more mole percent of ethylene, about 10 or more molepercent of

and up to a total of about 10 mole percent of one or more hydrocarbonolefins, with an alcohol or a primary amine which contains one or moreolefinic bonds, to form a second polymer having side chains with saidolefinic bonds; and (b) crosslinking said second polymer using a sulfuror peroxide cure system; and wherein: R¹ is methyl or hydrogen; and R²is hydrocarbyl or substituted hydrocarbyl.
 2. The process as recited inclaim 1 wherein said first polymer is an elastomer.
 3. The process asrecited in claim 2 wherein each R² is independently alkyl containing 1to 6 carbon atoms.
 4. The process as recited in claim 2 wherein R² ismethyl.
 5. The process as recited in claim 2 wherein said first polymeris ethylene/methyl acrylate dipolymer.
 6. The process as recited inclaim 2 wherein said first polymer is ethylene/alkyl acrylate copolymer,wherein each alkyl contains 1 to 6 carbon atoms.
 7. The process asrecited in claim 1, 2 or 5 wherein a transesterification is carried out.8. The process as recited in claim 7 wherein a transesterificationcatalyst is present.
 9. The process as recited in claim 8 wherein saidcatalyst is a tetraalkyl titanate or a tin compound.
 10. The process asrecited in claim 7 wherein said alcohol has the formulaHR³(CR⁴═CR⁵R⁶)_(t)CH₂OH(III) wherein R³ and each R⁵ are eachindependently a covalent bond, alkylene or alkylidene, and R⁴ and R⁶ areeach independently hydrogen or alkyl, and t is 1, 2 or
 3. 11. Theprocess as recited in claim 7 wherein said alcohol is one or more ofoleyl, linoleyl or linolenyl alcohols.
 12. The process as recited inclaim 1 wherein during (b) said first polymer is also present, providedthat said second polymer is at least 20% by weight of a total of saidfirst polymer and said second polymer.
 13. A composition comprising: (a)a polymer made by transesterifying or amidating a first polymerconsisting essentially of about 10 or more mole percent of ethylene,about 10 or more mole percent of

and up to a total of about 10 mole percent of one or more hydrocarbonolefins; with an alcohol or a primary amine which contains one or moreolefinic bonds, to form a second polymer having side chains with saidolefinic bonds; and (b) a sulfur or peroxide cure system; and wherein:R¹ is methyl or hydrogen; and R² is hydrocarbyl or substitutedhydrocarbyl.
 14. The composition as recited in claim 13 wherein saidpolymer is an elastomer.
 15. The composition as recited in claim 14wherein each R² is independently alkyl containing 1 to 6 carbon atoms.16. The composition as recited in claim 14 wherein R² is methyl.
 17. Thecomposition as recited in claim 14 wherein said first polymer isethylene/alkyl acrylate copolymer, wherein each alkyl contains 1 to 6carbon atoms.
 18. The composition as recited in claim 14 wherein saidpolymer is an ethylene/methyl acrylate dipolymer.
 19. The composition asrecited in claim 13 wherein said first polymer is also present, providedthat said second polymer is at least 20% by weight of a total of saidfirst polymer and said second polymer.
 20. A composition comprising: (a)a polymer consisting essentially of about 10 or more mole percent ofethylene, about 10 or more mole percent of

and up to a total of about 10 mole percent of one or more hydrocarbonolefins; and (b) a sulfur or peroxide cure system; and wherein: R¹ ismethyl or hydrogen; and R² is hydrocarbyl or substituted hydrocarbyl,provided that at least 0.5 mole percent of R² contains olefinicunsaturation.
 21. The composition as recited in claim 20 wherein saidpolymer is an elastomer.
 22. The composition as recited in claim 21wherein each R² which does not contain unsaturation is independentlyalkyl containing 1 to 6 carbon atoms.
 23. The composition as recited inclaim 21 wherein R² which does not contain unsaturation is methyl. 24.The composition as recited in claim 22 said polymer is a copolymer ofethylene and (I) only, wherein R² which does not contain unsaturation ismethyl.
 25. The composition as recited in claim 20 wherein a secondpolymer is also present, provided that said first polymer is at least20% by weight of a total of said first polymer and said second polymer,and said second polymer consisting essentially of about 10 or more molepercent of ethylene, about 10 or more mole percent of

and up to a total of about 10 mole percent of one or more hydrocarbonolefins, wherein: R¹ is methyl or hydrogen; and R² is hydrocarbyl orsubstituted hydrocarbyl, provided that at least none of R² containsolefinic unsaturation.
 26. The product of the process of claim
 1. 27.The product of the process of claim
 7. 28. The process as recited inclaim 1 wherein said first polymer is dried before step (a).
 29. Theprocess as recited in claim 7 wherein said first polymer is dried beforestep (a).